300 Win Mag starting point for a load?

knightcc

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Hi Everyone

I picked up my first 300 Win Mag. It's a Rem 700 Custom Mountain with a 24" barrel. I was wondering if anyone has any information they would like to share in terms of powder and bullet combinations as I am looking to work up a load for this gun. I will use this rifle for elk and moose so I would like it to shoot a 180 grain Partition, Accubond or Barnes bullet well if possible. Any help you could offer would be great. Thanks in advance.
 
Your best bet is to buy the Barnes and the Nosler manuals and start researching what you think is your best bet for each of the bullets. What I shoot in my .300 is not necessarily any use to you at all.

I use H4831 for the lighter bullets, and H1000 for the 180 and 200 grain loads I shoot.
 
In my Tikka I'm shooting a Barnes 180 TSX with 78 gr of IMR 4831 (I'll have to double check my load data when I get home) and it does just under 1 MOA which is good enough for me.
 
RL 22 works well with the 180's I have tried in a few 300 win-mags. My loads seem to be at the top of the max powder compressed loads in the Nosler manual, so just proceed with caution. Just do some load development and you will never look back. I also recently had some luck with H-1000 in the 200 grain accubonds.
Even better if you have access to a Chronograph
Every rifle is different, even if you go from that same rifle make and model in the same year.
 
I have shot enough 300 Winchester rifles that I can assure you if it wont shoot accurately with a 180 grain bullet over 74-76 grains of Reloader 22 it probably wont shoot at all.

Bugholes...Lots of bugholes.
Give it a shot. ;)
 
All the 300 Win Mags I have owned have liked 4350. Some have also liked 4831 for hte heavier end of hte bullet. 4350 and a 165 grain Boat tail is a hard combo to beat for shooting anything from Deer to Moose. The very large moose in my Avitar was shot with exactly that combination.
 
I forgot to add that you can expect 3100fps or a bit more.

Bugholes and 3100fps!
Doesn't get any better man! :D
 
All the 300 Win Mags I have owned have liked 4350. Some have also liked 4831 for hte heavier end of hte bullet. 4350 and a 165 grain Boat tail is a hard combo to beat for shooting anything from Deer to Moose. The very large moose in my Avitar was shot with exactly that combination.

:agree:
 
When I'm testing a new .300 Winchester Magnum, my control load is always 73.0 grains of IMR 4831 behind a decent 180-grain bullet (often a Hornady because it's cheap and always available). If this combo doesn't give me something in the vicinity of one-inch groups and 3,000 feet-per-second, I figure that something is wrong with the rifle. Some combos give higher velocities, and some combos give a smidgen better accuracy; however, this is is a standard load that always seems to work.
 
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Just as a note, my friend has an old loading manual from the late 60's/early70's that lists 77gr/200gr, 79gr/180 and 85gr/150gr as max with IMR 4831. That is substantially higher than the newer publications list. I get my best accuracy with 150gr Smk hpbt's with 77, and 180gr hornady sst's at 75gr. I'm boggled as how to cram 85 in the case but I never have tried either. Both loads are just starting to sharpen the edges of the primers.
 
78gr,H4831SC,165/168 Ballisitc Tips 25 3/4 A-Bolt Factory
75gr,H4831SC,180 gr Partitions same A-bolt
Six months to reach , it's Max Loads
Recommends not to Copy but to work your own way - Biggs
 
Just as a note, my friend has an old loading manual from the late 60's/early70's that lists 77gr/200gr, 79gr/180 and 85gr/150gr as max with IMR 4831. That is substantially higher than the newer publications list. I get my best accuracy with 150gr Smk hpbt's with 77, and 180gr hornady sst's at 75gr. I'm boggled as how to cram 85 in the case but I never have tried either. Both loads are just starting to sharpen the edges of the primers.

There is a very good reason for that. The 4831 you got 30 or 40 years ago is not the same as the stuff you buy today. I still have a small part of a 20 lb keg of 4831, it is H, but this was from before there was IMR 4831 so there is no reference to H or IMR in the old loading books. If that manual is really from the 60s, I would bet is doesn't say IMR or H, just 4831. I bought this keg in the 70s and the powder was made in the late 40s or early 50s and stockpiled in 1000 lb barrels by the military. This is surplus podwder from military stores that Hogdon bought up, packaged in 1, 8 and 20lb lots, and re-sold for $1 a lb. The load I worked up and still use in a 7 Rem Mag is 68 grains under a 162 grain bullet for 3050 fps. YOU DO NOT WANT TO USE THIS LOAD WITH CURRENT BATCHES OF H- or IMR-4831, you are almost guaranteed to blow up the gun.

People talk a lot about lawyered loads etc. That is non-sense. The pressure testing equipment of 40 years ago was no where near as good as what we have today. On top of that, the modern powder is very different too, even if it has the same number on it. If you are using published loads from a reputable source, especially when they have have pressure figures attached to them, why on God's green earth would you not want to believe that information and instead rely on data 40 years old.
 
my, I'm a meat stick. It states Hodgdon4831, all other powders listed for this caliber were IMR. He has 2 books, one is the lee 1st edition and the Lyman seems to be close in age. I do not remember which had this in it, and which pre-dated this caliber. I do have a picture in my phone of that page from the book, the picture does not tell me which book though.
 
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